Variable-weight control device



Nov. 25, 1941 A. L. SMYLY 2,263,596 VARIABLE-WEIGHT CONTROL DEVICE Filed Jan. 6, 193

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fieyezetar Patented Nov. 25, 1941 UNITED STATES PATENT OFFICE VARIABLE-WEIGHT CONTROL DEVICE Arthur L. Smyly, Chicago, Ill.

Application January 6, 1938, Serial No. 183,589

8 Claims.

The present invention relates to balanced control valves, for example, those used for control of gas volume and pressure.

The use of balanced control valves is old, as typified by the feeding of illuminating gas from a pressure gas-tank to=a service main. Such valves are designed for more or less automatic operation to produce greater pressure and feed greater volume to the service main at times of greater demand, and to cut the pressure and volume as demand decreases. Valves heretofore used have a weighted valve stem balancedagainst the pressure of gas. Variation of pressure causes the valve stem to move in directions to control the opening thereinto control the supply to the lower pressure service main. Various devices'have' been employed for varying the weight effective on the valve stem in such" operation. The present in-' vention provides a simple device for such purpose.

The primary object of the invention is to provide a unitary changeable weight device movable in a vertical plane and carrying liquid which moves in movement of the device to change the effective Weight of the device against a given: support, according to the position of the device.

A particular objectof the invention is to provide a pivoted arm with liquid wells on each side of the pivot, interconnected for flow of liquid from well to well in the rocking of the device.

Various other and ancillary objects and advantages of the invention will be apparent from the following description and explanation of one embodiment thereof shown in the accompanying drawing in which:

Fig... 1 represents a general view ofthe device as it may be connected to a balanced valve, and also illustrates a typical valve for which the invention may be used.

Fig. 2 represents a vertical view of the device largely in vertical cross-section.

Fig. is a vertical cross-section of the device on the line 33- of Fig. 2, showing detail in the mounting of the rocking arm.

Fig. 4 is a cross-section of one well on the line 4-4 of Fig. 2, showing particularly the character of the block used in the well.

Various changes and modifications of the spe c'ific structure of the drawing are contemplated as falling within the scope of the invention as defined in the appended claims.

Generally, the preferred form of the device comprisesa pivotally movable bar having a gen erally horizontal position, mounted to tilt in a vertical plane with its axis intermediate its ends, and having two mercury or other liquid wells spaced along the bar and interconnected by means movable with the bar, providing a passage-way from well to well. Preferably the passage-way is provided by the bar itself having a tubular form. The purpose of two wells spaced along the bar is to assure a flow of liquid between them as the position of the bar changes. The position of the wells with relation to" the pivotal axis is not an exact one, because in any event there" will be a change in level. The wells may be on thesame side of the pivot, or opposite sides, or one may be at the pivot, without changing the nature of its operation. However, it is preferred to have the wells on opposite sides, whereby one side counter-balances the other. Such arrangement gives a minimum of inertia to the device, compared to one in which both wells are on the same side of the pivot with the possible requirement of other counter-balancing Weight on the other side.

Heretofore, relatively moving wells for mercury have been employed in such a relation that mercury is shifted back and forth according to the relative position of the wells. Such devices have been connected by flexible tubing, particularly rubber. These deteriorateand frequently give trouble; particularly loss of mercury at a critical time. The present device overcomes prior difficulties by providing a rigid unit and a pivotal mounting therefor. It also provides a simple structure with a number of adjustable features whereby action of a valve may be varied for a wide range of conditions.

In the drawing, Fig. 1 shows an illustrative valve operated by one form of the invention. The particular valve is a well known commercial form and no part of it is essential to the present invention except the weighted valve stem to be inside a cylinder forming an upper casing 2| capped by cover 22 through which the stem [1 projects at 23. A weight 24 may be placed on the bell 20 inside casing 2|. The pressure in the outlet chamber I4 is communicated through valved pipe 25- to thespace' under the bell 20.

The Weight of and on stem 11 is sufilcient to be balanced by the upward pressure on the inside of the bell.

It is frequently desirable to increase the active weight of the stem as the stem descends. The present invention does this as follows:

Connected to the top 23 of stem I1 is a link 30 pivoted at one end to a fitting 3| which is secured to stem top 23 by a threaded adjustment, and at the other to a threaded fitting 32 carrying a well 33 for a liquid weight, preferably mercury M. This well 33 is paired by a well 34, and each is mounted on opposite ends of a rocking bar 35. The bottoms of the wells are interconnected by a rigid tubular connection which tilts with the bar. This may be a special tube for the purpose, but it is preferably provided by a tubular form for bar 35. Therefore, bar 35 has a passage-way 36 therein connecting through suitable fittings at the wells, with the bottom interiors of the wells. Except for such fittings, the wells 33 and 34 are shown as duplicates. Each has a glass cylinder 38 between bottom plate 39 and ring plate 40, clamped together by bolts 4| threaded into the ring plate to project therefrom for the receipt of a removable cover plate 4%. Inside the well a block 42 is provided with holes 43. Each block is fixedly mounted on a threaded stem. 44 which can be turned, engaging a threaded hole 45 in the top plate, to raise and lower the block by thumb-screw head 46. Plugs, such as the long plug 41 and the stopper-like plug 48 may be provided for one or more holes of either block.

The bottom of plate 39 at the valve side, has a fitting 50 receiving the fitting 32 on link 30. Fitting 50 also is threaded onto the end of bar 35 and provides a passage-way of right-angular form for liquid from the hollow interior 36 of bar 35 to the well 33. A needle valve 52 controls the opening to prevent surging of liquid back and forth as the arm 35 may be rocked. The other well 34 has a fitting 53 threaded onto the end of bar 35, a connecting passage-way 54 from the end of bar 35 to the interior of well 34, and a screw plug 55, by means of which liquid may be drained out of the system.

The bar 35 is fixedly mounted for vertical motion as .on a pivot, and the position of the pivot is adjustably movable along the bar, and vertically adjustable. A fixed horizontal base 60 has a bolt 61 for mounting a right-angular bracket 62. This bracket has a slot 63 in its horizontal leg, by means of which it is mounted in horizontal adjustability to base 60. The vertical leg of bracket 62 has duplicate vertical slots 64 through. which bolts 65 hold a vertical standard 66 with vertical adjustment. Standard 66 carries extension plates 61 and 68 on two opposite faces in which a block 69 rocks on pivots 10. Block 69 is bored to receive bar 35. Screw H holds the bar fixed in the block and permits adjusting the effective pivot of the bar along the bar. One of pivots 'IIJ carries a gear 12 meshing with a gear train 13 to turn a'needle 14 on dial 75 to indicate the position and functioning of the valve' operated by the structure. If desired a bracket 16 may be carried by standard 66 to provide an adjustable stop 11 for the rocking arm 35 on one side, and a similar bracket I8 and stop 19 on the other side. I

The geared. indicator is merely representative of any known means to indicate one record. This may be supplemented or replaced by a remotely located indicator or recording device, as generally illustrated by the electrical connection 83 to remote electrical device 8|.

As shown, the wells are balanced on the fulcrum of the bar, but the bracket 62 may be moved to the right in Fig. 1, while the screw 1| is loosened, thus shifting the fulcrum to one side of the center, as for example the dotted line position designated 66 The angularity of link 30 may be changed to take components of the added weight. Standard 66 may be raised. The position of the blocks may be changed, or some of its holes plugged or unplugged. For example, suppose that the blocks are raised well above the level of the mercury. A tilt clockwise in Fig. 1 may result in all the mercury flowing into well 33 to weight the valve stem. Now, if the blocks are each immersed in the mercury when the bar is not tilted, th depth of mercury will be much greater, and a similar incline of the bar will transfer less mercury to weight the valve stem.

It is readily seen that all the permissible adjustments give the control device a flexibility such that it can be adjusted for different conditions peculiar to each installation. The device is permanent without deteriorating parts, is rigid, yet delicately balanced to perform its functions.

It is contemplated that the vertical swinging may be other than that provided by a pivot, for example as byrockers, or other suitable mounting. The important pointis that two wells are rigidly associated and interconnected in a unitary device to move in a vertical plane to shift'the liquid from well'to well as the device so moves; The normal operation of the device is to exert weight on the valve stem, but it may be designed, adjusted and be operated to pull as well as push, or to pull only. Therefore, the operative connection to the valve stem is one to take both pull and push. Where a push only is obtained, it is obvious that the device need but rest on the valve stem I1. These and various other changes and modifications are contemplated.

It is also to be understood that the device is not limited to use as shown. The illustrated valve may be one with a flexible diaphragm instead of the drum. Likewise, the valve may be used to load an auxiliary or pilot valve, the operation of which provides variable pressure for the actuation of a larger main supply valve in a well known manner.

I claim:

1. A control device for a weighted stem of a balanced valve, comprising a support, a bar pivoted in said support for rocking in a vertical plane and adapted to be operatively associated with said stem, two wells for liquid carried by the bar to assume different levels in rocking the bar, means providing a passage-way for the fiow of liquid from well to well in the rocking of the bar, and means in a well for immersion in liquid therein to adjust the distribution of liquid between the wells, the passageway entering each well at a level below the liquid level of the well, whereby the liquid by gravity tends to seek a common level in changing the angularity of the bar.

2. A control device for a weighted stem of a balanced valve, comprising a support, a, bar pivoted in said support for rocking in a vertical plane and adapted to be operatively associated with said stem, two wells for liquid carried by the bar at the ends thereof, each well at its bottom having a fitting with a passage-way connecting the bottom of the well with the end of the bar. said bar being hollow from end to end whereby to connect the bottoms of each well for the transfer of liquid from; well to well in the rocking of the bar, the hollow of the bar passing substantially through the line of the pivot.

3. A control device for a weighted stem of a balanced valve, comprising a support, a bar pivoted to said support for rocking in a vertical plane and adapted to be operatively associated with the said stem to vary the weight effective on said stern, two wells for liquid carried by the bar to assume different levels in rocking the bar, said wells having a liquid passageway between their bottoms, and a needle valve in said passageway, whereby liquid in said wells seeks a common level in changing the angularity of the bar.

4. A control device for a weighted stem of a balanced valve, comprising a support, a bar pivoted to said support for rocking in a vertical plane and adapted to be operatively associated with the said stem to vary the weight effective on said stem, two wells for liquid carried by the bar on opposite sides of the pivot to assume different levels in rocking the bar, said wells having a liquid passageway between their bottoms, and a needle valve in said passageway, whereby liquid in said wells seeks a common level in changing the angularity of the bar.

5. A control device for a weighted stem of a balanced valve, comprising a support, a bar pivoted to said support for rocking in a vertical plane and adapted to be operatively associated with the said stem to vary the weight effective on said stem, two Wells for liquid carried by the bar on opposite sides of the pivot to assume different levels in rocking the bar, said wells having a liquid passageway between their bottoms, and means to shift the position of the pivot along the bar relative to the two wells.

6. A control device for a weighted stem of a balanced valve, comprising a support, an element pivoted in said support to rock in a vertical plane, a bar adjustably mounted in said element to be fulcrumed adjustably between its ends, said bar being adapted to be operatively associated with said stem to vary the weight effective on said stem, two wells for liquid carried by the bar to assume diiferent levels in rocking the bar, said wells having a liquid passageway between their bottoms, whereby liquid in said wells seeks a common level in changing the angularity of the bar.

7. A control device for a weighted stem of a balanced valve, comprising a support, a hollow bar pivoted on said support for rocking in a, vertical plane and adapted to be operatively associated with said stem to vary the weight effective on said stem, two wells for liquid secured to the ends of said bar with the bottoms of the wells in communication with the hollow interior of said bar, and a needle valve to control the flow through the communication between said two Wells, whereby liquid in said wells seeks a common level through said bar in changing the angularity of the bar and according to the opening at the needle valve.

8. A control device for a weighted stem of a balanced valve, comprising a support, a fixture pivoted to said support for rocking in a vertical plane, a hollow bar adjustably mounted along its length in said fixture to rock therewith in a vertical plane, said bar being adapted to be operatively associated with said stem to vary the weight efiective on said stem, two wells for liquid secured to the ends of said bar with the bottoms of the wells in communication with the hollow interior of said bar, whereby liquid in said wells seeks a common level through said bar in changing the angularity of the bar.

ARTHUR L. SMYLY 

